Large fins vs. Medium fins for medium sized surfers...@ 130lbs Lakey rides size L, Filipe "always" rides size L @ 155lbs

casa_mugrienta

Duke status
Apr 13, 2008
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In regards to GG's "Pool Talk" thread:


Hope you don't mind me starting a new thread Greg, but I though the topic was really interesting and the "Pool Talk" title was a bit of a misnomer to the actual meat of the content.

I'd really like to hear your thoughts and others on this topic.

Any of you medium guys always riding large?

In general, have fins gotten smaller since FCS/Futures took hold? Were glass-ons any larger?

What's your specific philosophy in regards to sizing fins Greg?

How big is going to be too big for the rider?

In my personal experience larger fins are always faster but much more difficult in critical sections of the wave. At the same time for a weakling like myself it's easy to overpower some medium size templates, especially more upright ones, coming off the bottom.

From the footage Lakey's board looks a bit stiff...contrast with Filipe still looking loose on the large.



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casa_mugrienta

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Apr 13, 2008
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I'll add @ 150 I've got two Large templates in my possession to try -


Rusty Blackstix 3.0:

Side Fins – Height: 4.63" / Base: 4.45" / Area: 15.23" / Foil: V2

Center Fin – Height: 4.48" / Base: 4.37" / Area: 14.55" Foil: 50/50


Futures DHD:

Area15.8315.83
Height4.694.69
Base4.524.52
FoilBevel50/50
 

fishtank

Gerry Lopez status
Jun 20, 2010
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it really depends on the board, at 180 the usual choice is a large fin. have been riding the EA techflex in the board with a narrower tail and it feels good. have a few sets on hand and swap them out from time to time and see what feels best.
 

r32

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Apr 1, 2005
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Would love to see actual in-pool testing of fins with computers hooked up to measure data. So many shapes, size, length, position, and material combinations it's hard to keep track of.
 

CCKeith

Gerry Lopez status
May 13, 2014
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Boards are tiny with lots of rocker

They need something to push off of
its technique, theyh learned to ride bigger fins and the shaper has adjusted placemnt to allow it so, the rocker hasnt anytgiung to do with it
 

Senor Sopa

Billy Hamilton status
Mar 11, 2015
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its technique, theyh learned to ride bigger fins and the shaper has adjusted placemnt to allow it so, the rocker hasnt anytgiung to do with it
I think the bigger fins are a consequence of needing to overpower the concaves desire to stay flat.

To address GG. Yes, the fins are a foil, but small compared to the foil of the sunken rail on edge. The water displacement is the key.
 

griffinsurfboard

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Oct 31, 2004
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Mine plane on the flat side , outside foil is for suction not planing .

Everyone has felt their board planing on the fins in hollow surf - great feeling

Finding how to design that in all the time was the mission :)

I like this :

"I think the bigger fins are a consequence of needing to overpower the concaves desire to stay flat."
 
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jkb

Tom Curren status
Feb 22, 2005
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Same here.

However, both of these surfers are riding standard shortboards. No wider tailed stuff.
If we're talking a standard hpsb tail width (whatever that is), I'll usually go with a medium fin if the board has enough inherent drive on its own (straighter outline, flatter centerline rocker, ect....).

If the board has a lot of outline or rocker curve and doesn't feel drivey enough for me, then I'll use large fronts and a medium sized trailer.

If the board feels too loose, increase rear fin size. Too tight, decrease rear fin size.
 

Waterlogged05

Michael Peterson status
May 14, 2005
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Was thinking the same after seeing that kid Kei Kobiyashi rides Large JW fins and he cant be more than 140. Guy rides like a 5'6" standard shortboard. He shredz
 
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